Cinematographic apparatus



Dec. 8, 1925. 1,564,295

W. THORNER C I NEMATOGRABH I C APPARATUS Filed Sept. 12. 1922 InventorPatented Dec. 8, 1.925.

UNITED STATES 1,564,295 PATENT OFFICE.

WALTHER THORNEB, OF BERLIN, GERMANY.

CINEMATOGRAPHIC .AZPPARATUB.

Application filed September 12, 1922. Serial No. 587,668.

To all whom it may concern:

Be it known that I, WALTHER THORNER, a citizen of the German Republic,residing at Berlin, Germany, have invented certain new and usefulImprovements in Cinematographic Apparatus (for which I have filed appieation in Germany, September 20th, 1921), of which the following is aspecification.

This invention relates to a cinematographic apparatus which is adaptedto be used bothv forreproducing and for photographing cinematographicpictures and which belongs to that class of apparatuses in which thefilm strip is continually moved, the eflect of the continuity ofmovement being compensated by corresponding movement of a system ofreflectors forming a rotating reflector ring having its reflectors soarranged that they are adapted to reflect rays of light impingingthereon towards the inside of the reflector rin The invention is animprovement of cinematographic apparatuses of the said kind, the purposeof the improvement consisting therein to avoid disturbances of thenormal function of the apparatus by unintentional relative movements ofthe reflector ring and the transporting means of the film strip, suchunintentioned relative movements occurring in known constructions forinstance by waste of toothed gearings, etc.

According to the invention any unintentional relative movement betweenthe reflector ring and the transporting means for the film is avoided byfirm connection between the reflector ring and the transporting memberfor the film. Such firm connection between the two members of theapparatus is not in conformity with the require ment that the reflectorring and the film strip must be moved in known construction in oppositedirections in order to secure the effect of compensating the continuousmove ment of the film strip. This difliculty is avoided in the newconstruction accordin to the invention thereby that in the path 0 thelight rays between the guide or window for the film strip and thereflector ring an optical system is inserted which comprises besides theobjective further optical means including reflectors which are sodesigned .that wandering light rays are moving in the same rotatingdirection before entering said objective and further optical means andafter leaving them. Suitable optical means are the combination of aroof-shaped prism and of a simple rectangular prism arranged at o positesides of the objective.- In such com ination the roof-shaped prismcounteracts the reversion in the wandering of the light rays produced bthe objective in the same way as it was itherto done by the movement ofthe film strip and the reflector ring in o posite directions.

Prefera bl the rotating reflector ring firmly connecte with atransporting wheel for the film is arranged in such a way that the axisof rotation is substantially vertically positioned, the bearing for thevertical axis beingbetter adapted to take up the stress of the heavystructure.

An embodiment of the invention is illustrated on the accompanyingdrawing in a substantially diagrammatic form.

- 1 Figure 1 is an axial section through the reflector ring of acinematographic apparatus and through the film guide connected to saidreflector ring, made in accordance with the present invention.

Figure 2 is a plan view of Figure 1.

The axis of rotation of the reflector ring and transporting wheel isdesignated a. b is the bottom of the reflector ring whereon thereflectors c of the ring are positioned. The reflectors are reflectingtowards the inside of the rin d is the roof-shaped prism, e theobjective and f a rectangular prism. These three elements form anoptical system inserted in the path of therays between the reflectors cof the'rin and the film Z. The film transporting mem er comprises twotransporting wheels 9 and '5 arranged in some distance from each otherand connected with each other by rods k and firmly connected with thereflector ring by connecting arms h.

The film l is shown as runnin through a fixed guide n forming a so-caled window suitably dimensioned in dependence from the dimensions of thepictures of the film. The plane of the film guide at is inclined to theline of direction from the film guide towards the centre of thereflector ring in such a way that the line of direction from the filmguide towards the axisof the objective or the point where it meets thereflecting surface of the rism f. is rectangular to the plane of saifilm guide.

m is a contact roller pressing the film against the two transportingwheels g, i.- o and p are two, reflectors inserted in the are projected.in uprig and p are arranged one above the other and adapted to eflect adisplacement of rays so as to bring the rays coming from the object tothe inside of the reflector ring or the rays coming from the pictures onthe film 1 from the inside of the reflector ring to outside of same andto the screen. The reflectors o, p are so inclined with relation to eachother that the images which usually are running in'lying positionthrough the film guide a the reflector The operation of the device is asfollows:

Supposing the pictures of a film Z are to be projected on a screen notshown on the drawing. The axis a of the reflector ring is rotated in anydesired speed either by hand or by a motor. Then at the same time thefilm Z is drawn through the film guide n with a velocitydepending fromthe size of the transporting wheels g and i which enter with their teethinto holes at 'the two edges of the film as usually. The 1i ht comingfrom the'pictures on the film Z is reflected by the reflecting surfaceof the rectangular rism f, passes through the objective e and impingeson the roof-shaped reflecting surface of the prism d and is reflectedthereby towards the reflectors 0 of the reflector ring.. The .reflectorsc reflect the light rays towards the reflector 0 which on its sidereflects the light towards the reflector p which finally reflects themto-- wards the screen.

The firm connection between the reflector ring 0 and the transportingwheels 9, i secures absolute conformity of the movements of thereflector ring and the film.

VVhatI claim is:

1. A cinematographic apparatus comprising in combination a rotatable rinof reflectors'having their reflectin sur aces on the inside of the ring,a .gui e for a film strip, a transporting wheel for the film coaxiallywith and axially displaced to said reflector ring and in firm connectiontherewith, an objective and furtherpptical means includingreflectorswithin the path of light rays between said film guide and reflectorring, saidfurther 0 tical means provided between the film gui e and thereflector ring flectors having their reflectin in addition to theobjective ada ted to compensate the image reversion pro need by theobjective in the direction of the rotation of the reflectorring.

2'. A cinematographic apparatus compris. ing in combination a rotatablerin '0 resur aces on the inside of the ring, a gui e' for a film strip atransporting ring member for the film in firmconnection with saidreflector ring'and coaxially therewith, an objective t position throughmeans including reflectors within the path and an odd number ofreflectors within the pathof light rays between said film guide andreflector .ring.

3. A cinemato raphic apparatus comprising in combination a rotatablering of reflectors having their reflecting surfaces on the inside of thering, a guide for a film strip, atransporting wheel for thefilmcoaxially with and axially displaced to said reflector rin and in firmconnection therewith, the p la'ne of said guide being inclined to theline of direction towards the centre of' said reflector ring andtransporting wheel, an objective and further optical of light raysbetween said film guide and reflector .ring, said' further optical meansprovided between the film guide and the re- 4:. A cinematographicapparatus compris- I ing in combination arotatable ring of reflectorshaving their reflectlngsurfaces on the inside of the ring, a guide for afilm strip, ;a transporting wheel for the film coaxially with andaxially displaced to said reflector ring and infirm connectiontherewith, the plane of said guide being'inelined to the line ofdirection towards the centre of said reflector ring and transportingwheel, an optical system within-the path ofrays between said reflectorring and said film guide, said optical system positioned inside of thereflector ring and comprising a roof-shaped prism and a rectangularprism andan objective between said two prisms.

5. A cinematographic apparatus comprising a rotatable ring of reflectorshaving their reflecting surfaces on the inside of the ring, said ringhaving its axis of rotation pos tioned substantial y in verticaldirection, a guide for the film strip, atransportingmember for a filmstrip running through said guide in firm connection with said reflectorring, an objective and further optical means including reflectors withinthe path of light rays between said film guide and reflector ring, saidfurther optical means rovided between the film guide and the re eetorring in addition to the objective'adapted to compensate the imagereversion produced. by. the objective in the direction of the rotationof the reflector ring, and two reflecting members positionedone abovethe other and adapted to effect displacement of rays from outside toinside of the structure said last named two reflectors being sopositioned within the path of the light rays that the reflector ring isposltioned between them and the first mentioned tors havin theirreflecting surfaces on the inside of the rin a guide for a film strip,

2i transporting w eel for the-film coaxially with said reflector ringand in firm connectiontherewith, an ob]ective and furt er optical meansincluding reflectors within the path of light rays between said filmguide and reflector ring,

said. further optical' the re ector. ring in addition to the objectiveadapted to compensate the image-reverspecification.

WALTHER THORNER.

nieansffmrovided between the film guide and I

